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排序方式: 共有486条查询结果,搜索用时 31 毫秒
1.
Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
2.
Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm). 相似文献
3.
Dongari-Bagtzoglou AI; Warren WD; Berton MT; Ebersole JL 《International immunology》1997,9(9):1233-1241
CD40, a member of the tumor necrosis factor-alpha receptor family, is
constitutively expressed by cells of hematopoietic and non- hematopoietic
origin, including fibroblasts. Signaling through this receptor molecule
regulates inflammatory cytokine secretion by many cell types. Based on the
recently described cytokine secretory heterogeneity of fibroblast cell
subsets, we hypothesized that secretion of inflammatory cytokines by
gingival fibroblast cultures may be dictated by the existence of
differential proportions of cytokine- secreting subpopulations which
express high levels of CD40. After examining a large number of gingival
fibroblast (GF) cultures we find that the frequency of IL-6- and
IL-8-secreting cells mirrors the frequency of cells expressing high levels
of CD40 in these cultures. In addition, we demonstrate a direct functional
relationship between CD40 expression and IL-6 or IL-8 secretion by showing
that ligation of this molecule on GF, and CD40+ fibroblast subsets in
particular, up- regulates secretion of these cytokines in vitro.
相似文献
4.
5.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
6.
Charles Cody White Venkatraman Kothandaraman Jackie Lin Meghana Rao Alyssa Greenhouse William R. Barfield Russell Chapin Harris S. Slone Richard J. Friedman Josef K. Eichinger 《Arthroscopy》2021,37(1):17-25
PurposeTo determine whether change in shoulder position between internal rotation (IR) and external rotation (ER) during magnetic resonance arthrography (MRA) affects previously defined capsular measurements and to determine the utility of rotation in the diagnosis of instability.MethodsA retrospective study was conducted of patients who received a shoulder MRA with humeral IR and ER views. Patients with an arthroscopically confirmed diagnosis of instability and those with clinically stable shoulders, no history of instability, and no MRA findings of instability were identified and compared. Humeral rotation, glenoid retroversion, humeral head subluxation, capsular length, and capsular area using axial sequences of IR and ER views were recorded. Analysis compared IR, ER, and Δ capsular measurements between groups using independent t tests and univariate and multivariate regression.ResultsThirty-one subjects who were diagnosed with instability were included, along with 28 control subjects. Capsular length, capsular area, and humeral subluxations were significantly greater with ER compared with IR views (P < .001, P < .001, P < .001). Patients with instability displayed greater ER capsular length (P = .0006) and ER capsular area (P = .005) relative to controls. Multivariate logistic regression identified age, weight, sex, ER capsular length, and retroversion to be significant predictors of instability. ER capsular length independently predicts instability with 86% sensitivity and 84% specificity. Interobserver reliability using the intraclass correlation coefficient was rated good or excellent on all measurements.ConclusionVariance in humeral rotation during shoulder MRA significantly affects capsular measurements. Rotational views increase the utility of capsular measurements when assessing for instability, particularly capsular length and capsular area. The implementation of ER positioning enhances the ability to examine capsular changes of the shoulder joint and can assist in the diagnosis of instability.Level of EvidenceIII, retrospective comparative study 相似文献
7.
FJ Cowan JT Warner FD Dunstan WD Evans JW Gregory HR Jenkins 《Archives of disease in childhood》1997,76(4):325-329
The prevalence of osteopenia in children with inflammatory bowel disease (IBD) is unknown. The effect of nutritional state, disease activity, and steroid therapy on bone mineral content (BMC) of whole body, lumbar spine, and left femoral neck measured by dual energy x ray absorptiometry in 32 children with IBD was assessed by comparison with 58 healthy local school children. Using the control data, a predicted BMC was calculated taking into account bone area, age, height, weight, and pubertal stage. The measured BMC in children with IBD was expressed as a percentage of this predicted value (% BMC). Mean (SD) % BMC was significantly reduced for the whole body and left femoral neck in the children with IBD (97.0 (4.5)% and 93.1 (12.0)% respectively, p < 0.05). Of the children with IBD, 41% had a % BMC less than 1 SD below the mean for the whole body and 47% at the femoral neck. Reduction in % BMC was associated with steroid usage but not with the magnitude of steroid dose, disease activity, or biochemical markers of bone metabolism. In conclusion, osteopenia is relatively common in childhood IBD and may be partly related to the previous use of steroids. 相似文献
8.
Wanda D. Barfield 《Seminars in perinatology》2021,45(4):151407
Social disadvantage impacts the health of women and newborns throughout the life course. Contributing factors such as low educational attainment, unemployment, poverty, and lack of health insurance disproportionately affects minority women of reproductive age in the United States. This article reviews social disadvantage as it contributes to health status and health disparities for mothers and newborns in the United States and highlights the opportunities to improve social and structural determinants of health to address these gaps. 相似文献
9.
Joseph J. Kavolus Merrill A. Ritter Jorge G. Claverie William R. Barfield Daniel T. Lackland Robert T. Trousdale 《The Journal of arthroplasty》2014
Over the past decade the popularity of foreign medical aid has increased and gained notoriety. Operation Walk is a philanthropic organization dedicated to improving the ambulatory potential of patients in developing countries by providing free surgical treatment for patients who otherwise lack access to care of debilitating bone and joint conditions. During Operation Walk Mooresville's 2013 trip to Guatemala 40 patients prospectively completed a Likert Scale style survey. The 63-question survey assessed patient impressions and concerns regarding the care they receive as part of itinerant surgical aid trips. Mean scores were calculated and then concerns were ranked accordingly. We are aware of no other investigation assessing these sorts of patient centered perspectives for international surgical aid trips. 相似文献
10.
Lisa Romero Karen Pazol Lee Warner Lorrie Gavin Susan Moskosky Ghenet Besera Ana Carolina Loyola Briceno Tara Jatlaoui Wanda Barfield 《MMWR. Morbidity and mortality weekly report》2015,64(13):363-369